Yes, Bert was 1937 according to Bert. I've seen nothing else anywhere to support or contradict that... except folks going from memory and not from Bert.

Neither have I seen anything to suggest chanties were collected as work song on the Southern Empress. Hugill collected a Davies forebitter/demo at home and shelved it under "sea-going" chantey. Standard genre label convention even today.

On topic, I'm still trying to find out what A.L. Lloyd's own words/claims were. 'Learned' or 'heard' might work for song collecting... validating a work practice, not so much.